The raising puts Karoon Gas is a strong position to negotiate with buyers of stakes in its Australian and Brazilian projects. Those stake could fetch more than A$600 million, people familiar with the matter told The Wall Street Journal last week.

Karoon emerged as one of Australia’s most promising mid-sized explorers in 2009 when it discovered the Poseidon natural gas field offshore Western Australia state in a joint venture with ConocoPhillips. In February, PetroChina Co. acquired a 20% stake in Poseidon from ConocoPhillips for an undisclosed sum.